U.S. patent number 10,071,512 [Application Number 15/156,569] was granted by the patent office on 2018-09-11 for method for manufacturing liquid-ejecting head.
This patent grant is currently assigned to CANON KABUSHIKI KAISHA. The grantee listed for this patent is CANON KABUSHIKI KAISHA. Invention is credited to Hiromasa Amma, Yasushi Iijima, Takuya Iwano, Satoshi Kimura, Satoshi Oikawa, Kyosuke Toda, Naoko Tsujiuchi, Mikiya Umeyama, Yukuo Yamaguchi.
United States Patent |
10,071,512 |
Kimura , et al. |
September 11, 2018 |
Method for manufacturing liquid-ejecting head
Abstract
Provided is a method for manufacturing a liquid-ejecting head
whereby in die slide injection molding it is possible to stably
inject resin in secondary molding without damaging the shapes of
parts that were formed in primary molding. In order for that, in
the connecting section in which a convex section of a cover member
is inserted into an opening of a liquid-supply member, the closest
distance to the opening in the area where secondary resin is
injected is made larger than the gap between the opening and the
convex section. As a result, the resin is prevented from flowing
into a liquid path during the secondary molding.
Inventors: |
Kimura; Satoshi (Kawasaki,
JP), Yamaguchi; Yukuo (Tokyo, JP), Umeyama;
Mikiya (Tokyo, JP), Oikawa; Satoshi (Yokohama,
JP), Amma; Hiromasa (Kawasaki, JP), Iwano;
Takuya (Inagi, JP), Tsujiuchi; Naoko (Kawasaki,
JP), Iijima; Yasushi (Tokyo, JP), Toda;
Kyosuke (Kawasaki, JP) |
Applicant: |
Name |
City |
State |
Country |
Type |
CANON KABUSHIKI KAISHA |
Tokyo |
N/A |
JP |
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Assignee: |
CANON KABUSHIKI KAISHA (Tokyo,
JP)
|
Family
ID: |
56068597 |
Appl.
No.: |
15/156,569 |
Filed: |
May 17, 2016 |
Prior Publication Data
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Document
Identifier |
Publication Date |
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US 20160346968 A1 |
Dec 1, 2016 |
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Foreign Application Priority Data
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May 25, 2015 [JP] |
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2015-105134 |
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Current U.S.
Class: |
1/1 |
Current CPC
Class: |
B29D
22/003 (20130101); B29C 45/1635 (20130101); B29C
45/0003 (20130101); B41J 2/1752 (20130101); B29C
45/0062 (20130101); B41J 2/1404 (20130101); B29C
45/006 (20130101); B41J 2/01 (20130101); B29L
2031/7678 (20130101); B41J 2/14032 (20130101) |
Current International
Class: |
B28B
7/22 (20060101); B29C 45/00 (20060101); B29C
45/16 (20060101); B29D 22/00 (20060101); B41J
2/14 (20060101); B41J 2/01 (20060101) |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
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101992601 |
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Mar 2011 |
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CN |
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102036823 |
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Apr 2011 |
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CN |
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59-089163 |
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May 1984 |
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JP |
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2002-178538 |
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Jun 2002 |
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JP |
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2002-321374 |
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Nov 2002 |
|
JP |
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2012-192749 |
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Oct 2012 |
|
JP |
|
200406313 |
|
May 2004 |
|
TW |
|
Other References
Extended European Search Report in European Application No.
16001152.4 (dated Sep. 30, 2016). cited by applicant .
Amma et al., U.S. Appl. No. 15/156,583, filed May 17, 2016. cited
by applicant .
Oikawa et al., U.S. Appl. No. 15/151,880, filed May 11, 2016. cited
by applicant .
Iwano et al., U.S. Appl. No. 15/156,649, filed May 17, 2016. cited
by applicant .
Tsujiuchi et al., U.S. Appl. No. 15/157,909, filed May 18, 2016.
cited by applicant .
Iwano et al., U.S. Appl. No. 15/156,578, filed May 17, 2016. cited
by applicant .
Oikawa et al., U.S. Appl. No. 15/157,890, filed May 18, 2016. cited
by applicant .
Toda et al., U.S. Appl. No. 15/156,559, filed May 17, 2016. cited
by applicant .
First Office Action in Chinese Application No. 201610344114.7
(dated Jun. 11, 2018). cited by applicant.
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Primary Examiner: Bell; William P
Assistant Examiner: Swanson; Andrew L
Attorney, Agent or Firm: Fitzpatrick, Cella, Harper &
Scinto
Claims
What is claimed is:
1. A method for manufacturing a liquid-ejecting head that comprises
an ejection-element section that ejects liquid and a liquid-supply
section in which a liquid path for guiding the liquid to the
ejection-element section is formed; wherein a main mold, and a die
slide mold that can slide inside the main mold and in which a mold
for forming a first part of the liquid-supply section and a mold
for forming a second part of the liquid-supply section are arranged
in a direction of the slide are prepared; the method including: a
first molding process for forming the first part and the second
part by injecting resin into the mold for forming the first part
and into the mold for forming the second part with the main mold in
a closed state; a sliding process for sliding the die slide mold
and positioning and aligning the first part and the second part in
the direction of the slide; and a second molding process for
forming the liquid-supply section by bringing the first part and
the second part into contact by inserting a convex section of the
second part into an opening in the first part, and then injecting
resin for connecting the first part and the second part together;
wherein in the second molding process, a distance between an area
where the resin is injected and the opening is larger than a
distance between an inner wall surface of the opening and an outer
wall surface of the convex section.
2. The method for manufacturing a liquid-ejecting head according to
claim 1, wherein the inner wall surface of the opening and the
outer wall surface of the convex section are parallel in a
direction of the insertion.
3. The method for manufacturing a liquid-ejecting head according to
claim 1, wherein the inner wall surface of the opening and the
outer wall surface of the convex section are inclined with respect
to a direction of the insertion.
4. The method for manufacturing a liquid-ejecting head according to
claim 3, wherein a direction of the inclination of the inner wall
surface of the opening, and a direction of the inclination of the
outer wall surface of the convex section are a same direction with
respect to the direction of the insertion.
5. The method for manufacturing a liquid-ejecting head according to
claim 3, wherein a direction of the inclination of the inner wall
surface of the opening, and a direction of the inclination of the
outer wall surface of the convex section are different directions
with respect to the direction of the insertion.
6. The method for manufacturing a liquid-ejecting head according to
claim 3, wherein the convex section is in contact with an edge of
the opening.
7. The method for manufacturing a liquid-ejecting head according to
claim 1, wherein grooves are formed in the convex section.
8. The method for manufacturing a liquid-ejecting head according to
claim 1, wherein a tip end of the convex section and an entrance of
the opening are arranged at nearly a same position in a direction
of the insertion.
9. The method for manufacturing a liquid-ejecting head according to
claim 1, wherein a direction of the insertion is in a direction of
gravity.
10. The method for manufacturing a liquid-ejecting head according
to claim 1, wherein a wall thickness of the first part and a length
of the convex section of the second part in a direction of the
insertion are equal.
11. A method for manufacturing a liquid-supply member that
comprises a liquid path for supplying liquid, wherein a main mold,
and a die slide mold that can slide inside the main mold and in
which a mold for forming a first part of the liquid-supply member
and a mold for forming a second part of the liquid-supply member
are arranged in a direction of the slide are prepared; the method
including: a first molding process for forming the first part and
the second part by injecting resin into the mold for forming the
first part and into the mold for forming the second part with the
main mold in a closed state; a sliding process for sliding the die
slide mold and positioning and aligning the first part and the
second part in the direction of the slide; and a second molding
process for forming the liquid-supply member by bringing the first
part and the second part into contact by inserting a convex section
of the second part into an opening of the first part, and then
injecting resin for connecting the first part and the second part
together; wherein in the second molding process, a distance between
an area where the resin is injected and the opening is larger than
a distance between an inner wall surface of the opening and an
outer wall surface of the convex section.
Description
BACKGROUND OF THE INVENTION
Field of the Invention
The present invention relates to a method for manufacturing a
liquid-ejecting head for ejecting liquid like ink as drops.
Description of the Related Art
In a liquid-ejecting head that ejects liquid as drops for forming a
photograph, a document, a 3-dimensional structure and the like,
liquid paths for receiving the liquid from tubes or tanks and
directing it to plural ejection elements are formed. For example,
in the case of a color-inkjet printing head that receives plural
inks and leads those inks to corresponding ejection elements, flow
paths from the ink-supply openings to the ejection elements must be
prepared independently for each color of ink. It is also necessary
to have hollow internal construction in which the size of liquid
chambers for temporarily storing the respective inks can be
maintained to a certain extent, and that bends and surely guides
each of the inks to ejection elements for each color that are
arranged in a highly-dense narrow area. Therefore, in recent
liquid-ejecting heads, that hollow internal construction has become
complicated.
Typically, from the aspect of ease of manufacturing, lightness, and
anti-corrosiveness, the flow paths of a liquid-ejecting head are
often formed using a resin mold. In Japanese Patent Laid-Open No.
2002-178538, a method is disclosed whereby in primary molding,
plural parts for achieving the kind of complicated internal
construction described above are formed by injecting resin into
different locations inside the same mold, and then in secondary
molding, the plural parts are connected to each other and resin is
injected again in the connecting areas to combine these parts
together inside the same mold. Hereafter, this kind of
manufacturing method will be called `die slide injection molding`.
By employing `die slide injection molding`, it is possible to
manufacture molded parts having complicated internal structure with
high precision and good efficiency.
However, as in recent years, when parts have complicated hollow
construction as described above, there was a possibility that parts
that were formed during the primary molding would become deformed
due to pressure used for injecting resin during the secondary
molding. Particularly, when a hollow area that was formed during
the primary molding was located near the injection opening during
the secondary molding, there was a possibility that resin would
flow into that hollow area during the secondary molding and that
the volume of that hollow area would be reduced. In a
liquid-ejecting head, such hollow areas function as liquid paths
that supply liquid to plural ejection elements. When the volume of
a liquid path becomes less than the design value, or when the
liquid path for only one particular color of ink is reduced, the
effect also appears in the image, so the reliability of
liquid-ejecting head also decreases.
SUMMARY OF THE INVENTION
The present invention was invented to solve the problems described
above. Therefore, the object of the present invention is to provide
a manufacturing method for a liquid-ejecting head whereby in die
slide injection molding, the injection of resin during secondary
molding can be performed stably without damaging the shape of parts
that were formed in primary molding.
According to a first aspect of the present invention, there is
provided a method for manufacturing a liquid-ejecting head that
comprises an ejection-element section that ejects liquid and a
liquid-supply section in which a liquid path for guiding the liquid
to the ejection-element section is formed; wherein a main mold, and
a die slide mold that can slide inside the main mold and in which a
mold for forming a first part of the liquid-supply section and a
mold for forming a second part of the liquid-supply section are
arranged in a direction of the slide are prepared; the method
including: a first molding process for forming the first part and
the second part by injecting resin into the mold for forming the
first part and into the mold for forming the second part with the
main mold in a closed state; a sliding process for sliding the die
slide mold and positioning and aligning the first part and the
second part in the direction of the slide; and a second molding
process for forming the liquid-supply section by bringing the first
part and the second part into contact by inserting a convex section
of the second part into an opening in the first part, and then
injecting resin for connecting the first part and the second part
together; wherein in the second molding process, a distance between
an area where the resin is injected and the opening is larger than
a distance between an inner wall surface of the opening and an
outer wall surface of the convex section.
According to a second aspect of the present invention, there is
provided a method for manufacturing a liquid-supply member that
comprises a liquid path for supplying liquid, wherein a main mold,
and a die slide mold that can slide inside the main mold and in
which a mold for forming a first part of the liquid-supply member
and a mold for forming a second part of the liquid-supply member
are arranged in a direction of the slide are prepared; the method
including a first molding process for forming the first part and
the second part by injecting resin into the mold for forming the
first part and into the mold for forming the second part with the
main mold in a closed state; a sliding process for sliding the die
slide mold and positioning and aligning the first part and the
second part in the direction of the slide; and a second molding
process for forming the liquid-supply member by bringing the first
part and the second part into contact by inserting a convex section
of the second part into an opening of the first part, and then
injecting resin for connecting the first part and the second part
together; wherein in the second molding process, a distance between
an area where the resin is injected and the opening is larger than
a distance between an inner wall surface of the opening and an
outer wall surface of the convex section.
Further features of the present invention will become apparent from
the following description of exemplary embodiments (with reference
to the attached drawings).
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1A and FIG. 1B are perspective views of a liquid-ejecting
head;
FIG. 2 is an exploded view of the liquid-supply member;
FIG. 3A and FIG. 3B are views illustrating two parts that are
joined in secondary molding;
FIG. 4 is an enlarged cross-sectional view of the connection
between a liquid chamber and a cover member;
FIG. 5 is a view illustrating a mold for forming the liquid-supply
member;
FIG. 6A to FIG. 6C are cross-sectional views of the mold for
forming the liquid-supply member;
FIG. 7A to FIG. 7C are views illustrating steps for forming the
liquid-supply member;
FIG. 8A to FIG. 8C are views illustrating steps for forming the
liquid-supply member;
FIG. 9A to FIG. 9D are views illustrating another form of a
connecting section between a liquid-supply member and a cover
member; and
FIG. 10 is a view illustrating the connection between three parts
in secondary molding.
DESCRIPTION OF THE EMBODIMENTS
Embodiment 1
FIG. 1A and FIG. 1B are perspective views as seen from different
angles of a liquid-ejecting head H001 that is used in this
embodiment. The liquid-ejecting head H001 of this embodiment is a
color-inkjet printing head for printing images by ejecting 12
colors of ink. Each color of ink is received into a sub-tank H030
by way of a tube that is connected to a supply opening H010. After
that, the ink passes through a liquid-supply member H100 in which
independent liquid paths are formed for each ink color, and is
guided to an ejection-element unit H020. Plural ejection elements
that correspond to each ink are arranged in a row in the
ejection-element unit H020, and ejection signals are supplied from
an electric connection board H050 based on image data. The
individual ejection elements eject ink as drops in the Z direction
according to the ejection signals.
FIG. 2 is an exploded view of the liquid-supply member H100. In the
liquid-supply member H100, filters H101 that correspond to
individual storage chambers that correspond to the ink colors and
that are used for removing foreign matter from the liquid are
attached to positions that are connected to the sub-tank H030 in
which the individual storage chambers are formed. A liquid chamber
H110 is formed between the filters H101 and the ejection-element
unit H020 for connecting the two together. Liquid paths having
different amounts of bending and different lengths connect upper
openings for connecting with the filters H101 and lower openings
for connecting to the ejection-element unit H020 are individually
formed in the liquid chamber H110 and correspond to the 12 ink
colors. In this embodiment, the hollow internal construction of the
liquid chamber H110 having such a complicated shape is formed by
die slide injection molding.
FIG. 3A and FIG. 3B are views illustrating two parts that are
finally connected in die slide injection molding. In this
embodiment, after a liquid-supply member H100 has been formed by
molding as described above, a cover member H121 that has similarly
been formed by molding is provided so as to face the liquid-supply
member H100 from the +Y direction, and is connected as illustrated
in FIG. 3B. After the liquid chamber H110 is completed by die slide
injection molding, the ejection-element unit H020 and the filters
H101 are attached to complete the liquid-supply member H100.
FIG. 4 is an enlarged cross-sectional view of the connection
between the liquid chamber H110 and the cover member H121. The two
members are connected together by inserting a convex section H521
that is provided on the cover member H121 side into an opening H500
that is provided on the liquid-supply member H100 side. In order to
achieve a secure connection, the cross-sectional area of the
opening H500 is set to be just a little larger than the
cross-sectional area of the convex section H521, and the design is
such that a gap (distance) t1 is formed between an inner wall
surface of the opening H500 and an outer wall surface of the convex
section H521. Moreover, in order that the smoothness of the wall
surface of the liquid path H501 is maintained, the tip end of the
convex section H521 and the entrance of the opening H500 are
arranged in nearly the same position in the Y direction.
In the secondary molding, with the liquid chamber H110 and the
cover member H121 connected as illustrated in the figure, secondary
resin that melts both the liquid chamber H110 and the cover member
H121 is injected in the surrounding area. As a result, the
secondary resin flows into a space H131 that was formed between the
cover member H121 and the liquid-supply member H100, and both
members are completely connected. When doing this, in this
embodiment, the shortest distance t2 between the injection area of
the secondary resin and the opening H500 is designed so as to be
sufficiently larger than the gap t1 (t2>t1).
FIG. 5 is a view illustrating a mold for forming the liquid-supply
member H100 by die slide injection molding. The main mold K001 that
is used in this embodiment includes a stationary-side mold K100 and
a movable-side mold K200 that can be separated in the Z direction.
Further, a die slide mold K230 that is in the main mold K001 and
can slide in the X direction with respect to the main mold K001 is
provided belonging to the side of the movable-side mold K200. FIG.
5 illustrates the state of forming both the liquid-supply member
H100 and the cover member H121 in primary molding. The
liquid-supply member H100 is formed by injecting liquid resin
through valve gates K110 and K111 at a first molding position K210
inside the mold. The cover member H121 is formed by injecting
liquid resin through a valve gate K120 at a second molding position
K220 inside the mold. Furthermore, the liquid-supply member H100
and the cover member H121 that are formed in the primary molding
are connected by injecting liquid resin through valve gates K130
and K131 at a third molding position K225 inside the mold.
FIG. 6A to FIG. 6C are cross-sectional views of the main mold that
is illustrated in FIG. 5. FIG. 6A is a transparent view of the mold
illustrated in FIG. 5 as seen from the Z direction. FIG. 6B is a
cross-sectional side view as seen from the -X direction when the
mold is cut along a section S3-S3 in FIG. 5. FIG. 6C is a
cross-sectional side view as seen from the -X direction when the
mold is cut along a section S4-S4 in FIG. 5. Each of the valve
gates K110, K111, K120, K130 and K131 is designed to inject a
specified amount of liquid resin from its nozzle when
correspondingly forming a part at a molding position with the main
mold K001 in the closed state.
The valve gates K110, K111, K120, K130 and K131 of this embodiment
are all of the same type, and each has a cross section as indicated
by the dotted-line circle in the figure. Therefore, adjacent valve
gates must be arranged at a distance that is as least equal to or
greater than the diameter of the dotted-line circle, and the second
molding position K220 and third molding position K225 that are in
the same position in the X direction are provided in positions that
are shifted in the Y direction.
FIG. 7A to FIG. 7C and FIG. 8A to FIG. 8C are views illustrating
the die slide injection molding process for forming the liquid
chamber H110. These figures are transparent views of the mold
illustrated in FIG. 5 as seen from the Z direction.
In a first step, with the stationary-side mold K100 and the
movable-side mold K200 closed, the resin is flowed from the valve
gates K110, K111 that correspond the first molding position K210,
and from the valve gate K120 that corresponds to the second molding
position K220. As a result, the liquid-supply member H100 and the
cover member H121 are formed at the first molding position K210 and
at the second molding position K220 respectively, inside the mold
K001 as illustrated in FIG. 7A. In this embodiment, this first step
corresponds to a first molding process.
In a second step, the movable-side mold K200 is moved in the +Z
direction with respect to the stationary-side mold K100, and the
two molds are separated. In this second step of this embodiment,
both the liquid-supply member H100 and the cover member H121 are
taken to belong to the die slide mold K230, or in other words, the
movable-side mold K200.
In a third step, as illustrated in FIG. 7B, the cover member H121
is moved in the +Y direction together with a part-sliding piece
K221 that forms one side of the cover member H121. At the second
molding position K220, a mold for forming the cover member H121 is
such that the surface of the one side includes the die-slide mold
K230, and the surface of the other side includes the part-sliding
piece K221. In this embodiment, when the part-sliding piece K221 is
moved in the +Y direction, the cover member H121 that belongs to
that piece also moves in the +Y direction. The movement of the
part-sliding piece K221 is performed by a driving source (for
example, a hydraulic cylinder) that is different than that for
moving the movable-side mold K200 in the Y direction as described
above.
In a fourth step, as can be seen in FIG. 7C, the die-slide mold
K230 that is arranged inside the movable-side mold K200 is moved in
the +X direction, and the liquid-supply member H100 and the cover
member H121 are positioned and aligned in the X direction. As in
the case of the part-sliding piece K221, the driving source for
moving the die slide mold K230 is different than that for moving
the movable-side mold K200.
In a fifth step, as can be seen in FIG. 8A, the part-sliding piece
K221 is moved in the -Y direction to the third molding position
K225, and the cover member H121 is brought into contact at a
specified position of the liquid-supply member H100. As can be seen
from FIG. 3A and FIG. 3B already explained above, the cover member
H121 of this embodiment is assembled in a secluded position with
respect to the width area in the Y direction of the liquid-supply
member H100. Therefore, it is possible to prevent collisions
between the two members in the fourth step by, after the cover
member H121 has been moved out of the way in the +Y direction to a
retreat position in the third step, and positioning and alignment
of the liquid-supply member H100 has been performed in the fourth
step, moving the cover member H121 back in the -Y direction in the
fifth step. In this kind of fifth step, the position to where the
part-sliding piece K221 moves is shifted further in the -Y
direction than the position where the primary molding of the cover
member H121 was performed in the first step. In other words, the
part-sliding piece K221 of this embodiment is able to move to three
positions: the second molding position K220, the retreat position,
and the third molding position.
In a sixth step, the movable-side mold K200 is moved in the -Z
direction, and becomes closed with the stationary-side mold K100.
Then in this state, the resin that is compatible with both the
liquid-supply member H100 and the cover member H121 is flowed from
the valve gates K130, K131 to the third molding position for
connecting together the liquid-supply member H100 and the cover
member H121 as illustrated in FIG. 8B. In this embodiment, this
sixth step corresponds to a secondary molding process.
In a seventh step, the main mold K001 is opened, the part-sliding
piece K221 is moved out of the way in the +Y direction to the
retreat position, and the completed liquid-supply member H100
having a sealed hollow structure is pressed in the -Z direction. As
a result, the liquid-supply member H100 and the cover member H121
are connected, and the completed liquid-supply member H100 is
obtained.
In the primary molding process and the secondary molding process,
in order to flow the resin to each of the corners of the molds and
to form parts having complicated construction, injecting the liquid
resin at a somewhat high pressure through the valve gates with the
mold K001 closed is preferred. When doing this, when the resin for
the secondary molding is injected at high pressure in the area
around the thin-walled complicated parts that were already formed
in the primary molding, there is a possibility that the parts
formed in the primary molding will deform, or that the resin will
flow into the hollow spaces formed in the primary molding.
For example, referring again to FIG. 4, when the distance t2 is
less than the gap t1, there is a possibility that due to the
pressure when injecting the secondary resin, the secondary resin
may pass through the gap t1 and enter into the liquid path H501 of
the liquid-supply member H100. Particularly, when a series of steps
is performed with the -Y direction being the direction of gravity
as illustrated in FIG. 5, the liquid resin flowed in the secondary
molding process can easily pass through the gap between the opening
H500 and the convex section H521 due to gravity, and reach the
liquid path H501. When such a condition occurs, the volume of the
liquid path H501 decreases, and when used as a liquid-ejecting
head, it is not possible to sufficiently perform the role of
supplying liquid. By making the distance t2 sufficiently larger
than the gap t1 as in this embodiment, even when the convex section
H521 comes into contact with one of the inner walls of the opening
H500 due to the injection pressure, the space H131 does not expand
to the opening H500, and the distance between the both is
sufficiently maintained. Therefore, even when the resin for
secondary molding is injected and flowed with somewhat high
pressure, the resin does not reach the gap t1, and it becomes
possible to stably manufacture a highly reliable liquid-ejecting
head.
Moreover, the wall thickness of the liquid-supply member H100 and
the length of the convex section H521 of the cover member H121 are
nearly the same, and have a sufficient size for securing the both.
Therefore, even in the case that the secondary resin flows into the
space H131 between the wall of the liquid-supply member H100 and
the cover member H121 at somewhat high pressure, there is fluid
resistance due to the thickness of the wall of the liquid-supply
member H100, and it is possible to prevent deformation of the
liquid-supply member H100.
Other Embodiments
FIG. 9A to FIG. 9D illustrate other forms of a connecting section
between the liquid-supply member H100 and the cover member H121 to
which the present invention can be applied. In the embodiment
above, as illustrated in FIG. 4, the wall surface of the opening
H500 that is provided in the liquid-supply member H100 and the wall
surface of the convex section H521 of the cover member H121 are
parallel with the Y direction. However, the opening H500 and the
convex section H521 in FIG. 9A and FIG. 9B for example are inclined
with respect to the Y direction. FIG. 9A illustrates the case when
the opening H500 and the convex section H521 are inclined in the
same direction, and FIG. 9B illustrates the case when the two are
inclined in different directions.
When such an incline (taper) is formed, the direction in which the
mold used for forming the parts is removed in the step 2 after the
primary molding is limited according to the direction of the
incline of the taper. For example, in the case of FIG. 9A, the mold
used in the primary molding for forming the liquid-supply member
H100 can only be removed in the +Y direction. Therefore, when
opening the main mold in the second step, the liquid-supply member
H100 belongs to the side of the stationary-side mold K100 and is
separated from the die slide mold K230. On the other hand, in the
case of FIG. 9B, the mold that is used in the primary molding for
forming the liquid-supply member H100 can only be removed in the -Y
direction. Therefore, when opening the main mold in the second
step, the liquid-supply member H100 belongs to the die slide mold
K230 and is separated from the stationary-side mold K100 in the
same way as in the embodiment above. In either case, the cover
member H121 belongs to the side of the die slide mold K230 as in
the embodiment above.
When comparing both cases, the case of FIG. 9A where the area of
the opening is large during insertion could be said to make
insertion of the cover member H121 into the opening H500 easy. In
this case, as illustrated in FIG. 9C, construction is also possible
in which the tapered shape of the convex section H521 is used and
the edge of the opening H500 is brought into contact with the side
surface of the convex section H521. By bringing the both members
into direct contact as illustrated in FIG. 9C, it is possible to
suppress movement and deformation due to resistance force that is
received from the edge of the opening H500 even when the cover
member H121 receives the fluid pressure of the secondary resin.
Moreover, t1 essentially becomes 0, and the path to the liquid path
H501 is completely sealed, so it is possible to more completely
prevent the flow of the secondary resin.
As even another form, it is possible to form grooves in the convex
section as illustrated in FIG. 9D. By preparing such grooves,
improvement of the liquid filling characteristics, or durability
during liquid supply at the opening H500 can be expected.
In any of the forms illustrated in FIG. 9A to FIG. 9D, the
relationship t2>t1 is satisfied as in the embodiment described
above. Therefore, even when the secondary resin is flowed under
high pressure during the secondary molding, the resin does not
penetrate into the liquid path H501.
The gap t1 is opened into the liquid path H501, so when the gap t1
is too large, air bubbles or the like may occur in it and affect
the performance of supplying liquid to the liquid path H501.
Therefore, preferably the gap t1 is designed as small as possible
but not obstruct the process of inserting the cover member
H121.
Moreover, in the embodiment described above, the five valve gates
of the same form were used as illustrated in FIGS. 6A to 6C,
however, of course the present invention is not limited to such a
form. It is also possible to perform all of the molding using the
same single valve gate, or it is also possible to prepare a valve
gate having a different form for injecting different resins in the
primary molding and secondary molding. It is also possible to use
three or more valve gates having the same form or different forms
for one part according to the amount of liquid injected, and the
volume and shape of the molded part.
Furthermore, above, as illustrated in FIG. 3A and FIG. 3B, the case
of connecting the two parts that were formed in the primary molding
in the secondary molding was explained, however, the number of
parts could be more than two. For example, as illustrated in FIG.
10, the liquid chamber H110 can also be completed by bringing two
cover members H121 and H122 in contact with the liquid-storage
member H100 so as to face from the +Y direction and -Y direction.
In this case, in the third step, a second mold piece is moved out
of the away in the -Y direction opposite from the mold piece K221
described above, and in the fifth step, that mold piece is moved in
the +Y direction so that the cover member comes into contact with
the -Y direction side of the liquid chamber H110.
With the present invention described above, in the connecting
section between the liquid-supply member H100 and cover member
H121, the closest distance t2 to the opening section of the flow
area of the secondary resin is larger than the gap t1 between the
opening and the convex section, it is possible to prevent resin
from flowing into the liquid chamber during secondary molding.
While the present invention has been described with reference to
exemplary embodiments, it is to be understood that the invention is
not limited to the disclosed exemplary embodiments. The scope of
the following claims is to be accorded the broadest interpretation
so as to encompass all such modifications and equivalent structures
and functions.
This application claims the benefit of Japanese Patent Application
No. 2015-105134, filed May 25, 2015, which is hereby incorporated
by reference wherein in its entirety.
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